Principles of ventilation

Ventilation is the planned removal heat, smoke and fire gases from a burning structure - this in effect supplies cool fresh air. Ventilation in a large fire should happen as or before the interior rescue crews enter the building.

The benefits of ventilation include:

• Improved visibility - helps with the finding and rescue of victims,

• Less chance of disorientation inside the smoke filled building.

• Reduced temperatures at the scene

• Reduced possibility of backdraft or flashover (reduces the spread of fire)
• Safer conditions

• Better chance of victim survival:

• More easily located,
• Lower temperatures,
• Lower risk of smoke inhalation.

Ventilating the fire

Ventilation should take place at the highest point near the burning side of the building. In a single story house, open or remove the windows in the room where the fire is burning. Ventilation may be :

• vertical - opening through the roof,
• Horizontal - opening of door and windows.

Safety

Fires and firefighting is dangerous and we need to be aware of the risks.

• Always wear the correct personal protective equipment (PPE) and SCBA.
• Be aware of the possibility of smoke and flashback so work with the wind at your back or side when cutting vent holes or venting windows
• Vertical ventilation: Check roof stability and only have the minimum personnel on the roof. Always work from a roof ladder on a pitched roof. and have a secondary escape route from the roof. Remove crew from roof after ventilation hole is completed.
• Be ready to fight the fire - the ventilation supplies fresh oxygen to the fire and can lead to fire spread.

References

• https://www.firerescuemagazine.com/articles/print/volume-7/issue-5/truck-co-operations/the-why-when-of-ventilation.html
• https://www.firerescue1.com/fire-products/ventilation/articles/373277018-Methods-of-fire-ventilation-based-on-structure-type/
• https://www.firehouse.com/operations-training/training-drills/article/10466264/review-of-ventilation-principles-practices